I've tried this on, not exactly on a VL install, but on my android phone, and migrating from from ext2/3 to ext4 has left me with undesired side effects that forced me to wipe the thing and re-do it with < ext4

For simply ext4 support in kernel: Kernel 2.6.31.8 on my VL box mounts and reads it just fine. After upgrading e2fsprogs to version 1.41.3 (sw 12.2) I can also create ext4 systems.

As far as your root filesystem.. I agree with M0E-lnx; pick a version that supports ext4 during installation. Converting afterwards would be complicated. I really don't see any good reason to do so.

@nightflier: Thank you! I only needed to be able to read partitions formated with the ext4. I forgot I can install Vector light on ext3, THEN upgrade the kernel and make it read and write other ext4 partitions. Am I correct? Besides, ext3 uses slightly less resources it seems?Regards,Drazen